ReactiveCocoa/ReactiveCocoa — pull request #823 by jonsterling (2013-09-26 17:44:34+00:00)
Title: Generalized -distinctUntilChanged to RACStream

I realized this morning that `-distinctUntilChanged` doesn't actually use any kit which is specific to signals, as opposed to other streams. Seems to make sense to just move it to `RACStream`. Thoughts?